--- a/tests/test-evolve.t	Mon Jan 23 16:09:16 2017 +0100
+++ b/tests/test-evolve.t	Wed Jan 25 16:50:19 2017 +0100
@@ -701,6 +701,10 @@
   abort: cannot fold non-linear revisions
   (given revisions are unrelated to parent of working directory)
   [255]
+  $ hg fold --exact -r "4 and not 4"
+  abort: specified revisions evaluate to an empty set
+  (use different revision arguments)
+  [255]
   $ hg phase --public 0
   $ hg fold --from -r 0
   abort: cannot fold public revisions